JP6173447B2 - Reactor and process for the production of hydrogen sulfide - Google Patents

Description

The present invention relates to a reactor and process for the synthesis of hydrogen sulfide from elemental sulfur and hydrogen at elevated pressure and elevated temperature. The invention further relates to the use of a reactor to produce hydrogen sulfide with high yield and low H ₂ S _x content.

  Hydrogen sulfide is an industrially important intermediate product, for example for the synthesis of methyl mercaptan, dimethyl sulfide, dimethyl disulfide, sulfonic acid, dimethyl sulfoxide, dimethyl sulfone and for a number of sulfidation reactions. At present, it is mainly obtained from the treatment of mineral oil and natural gas and by the reaction of sulfur and hydrogen.

  Hydrogen sulfide converts sulfur from the element into the gas phase, typically by introducing gaseous hydrogen into the sulfur melt, and then converts it to hydrogen sulfide in an exothermic reaction with hydrogen. (Ullmann's Encyclopedia of Industrial Chemistry, 6th edition, 1998, Wiley-VCH).

  In order to achieve a sufficient reaction rate and high hydrogen sulfide yield, the reaction must be carried out at an elevated temperature relative to standard conditions. Depending on the intended further use, it may be necessary to prepare hydrogen sulfide produced at a pressure of> 5 bar. In this case, it may be advantageous to carry out the synthesis of hydrogen sulfide directly at the required pressure. This requires a further temperature rise to ensure that enough sulfur is converted to the gas phase. However, carrying out the synthesis of hydrogen sulfide at temperatures> 450 ° C. has the disadvantage that under these conditions hydrogen sulfide causes corrosion damage to the reactor material. Therefore, there is a need to construct a reactor that allows high conversion rates and at the same time avoids damage to components that at least hold the pressure of the reactor.

  One means for increasing the hydrogen sulfide yield is to increase the residence time of the hydrogen gas in the sulfur melt. This is done, for example, in US 2876070 and DE 102008040544 A1 by using a reactor having a gas collecting area in the form of an intermediate tray or cup arranged in the sulfur melt. However, this type of configuration only achieves hydrogen conversion> 96%. Although the conversion rate may be increased by increasing the number of gas collection areas, this may have the disadvantage that a larger reactor volume is required.

  The principle of increasing the residence time of hydrogen gas in the sulfur melt is also implemented in DE 102008040544 A1 by a reactor having a bed of irregular ceramic packing in the sulfur melt. This reactor achieves a conversion rate> 99%. However, this reactor design requires a constant hydrogen supply, because upon reduction or interruption of the hydrogen supply, the reaction gas can escape completely from the region of the irregular packed bed, and the irregularity This is because the packed bed can be filled with liquid sulfur. Therefore, such a reactor can only operate within a very narrow load range.

  A further means of increasing the reaction rate is the use of catalysts such as cobalt, nickel or molybdenum oxides or sulfides. This means is disclosed, for example, in US Pat. No. 2,863,725 and EP 2,256,612 B1, in the form of a reactor having a catalyst packed tube immersed in the sulfur melt and through which gaseous reactants flow. However, the disadvantages of these reactors are that they are operated at a pressure of <5 bar and that a large amount of catalyst is required as a result of the fact that the reaction of sulfur and hydrogen is mainly catalytic. It turns out that there is.

  Accordingly, an object of the present invention is to provide a reactor for producing hydrogen sulfide from sulfur and hydrogen, which ensures a high hydrogen conversion rate and a high purity of the produced hydrogen sulfide. It is. The reactor should also allow for the production of hydrogen sulfide at pressures> 5 bar, have a very compact design and ensure a very wide load range. In particular, in an integrated manufacturing system, it is more flexible to various loads than it has to allocate overdue due to the lack of flexibility that is not required by the integrated system at that time. A very wide load range that can react is advantageous. Finally, from a cost, maintenance, and safety standpoint, the reactor should be less prone to corrosion damage under the intended operating conditions. A particularly efficient reactor design is additionally desired for the energy required for preparing the sulfur melt and for the dissipation of reaction heat. Furthermore, it is desirable to minimize the amount of catalyst required and maximize the useful life of the catalyst.

To solve this problem, the present invention provides a final product gas comprising hydrogen sulfide and sulfur by an exothermic reaction of sulfur and hydrogen at an elevated temperature and elevated pressure relative to standard conditions. A reactor suitable for the continuous production of hydrogen sulfide in which the mixture P _final results,
A lower reactor area suitable for containing the sulfur melt, and a gas collection area suitable for containing the product gas mixture P _final at an elevated temperature and elevated pressure relative to standard conditions. Wherein said reactor is provided.

The reactor according to the invention further comprises at least two first cavities that do not hold pressure, and at least one suitable for controlling and supplying gaseous hydrogen pressurized per first cavities. Including two supply devices, the cavity is suitable for at least temporarily containing a product gas mixture P ₁ generated in an exothermic reaction and comprising hydrogen sulfide, sulfur and hydrogen , and the reactor comprises: A second cavity that does not hold one or more pressures, the second cavity being disposed over the first cavity and a product gas mixture occurring within the first cavity It is suitable for at least temporarily containing P ₁ and for the exothermic reaction of sulfur and hydrogen to produce further hydrogen sulfide and to produce a product gas mixture P ₂ .

  The hydrogen supply device is designed so that the first cavities can be supplied with hydrogen independently of each other. Thus, the amount of sulfur and hydrogen supplied in each cavity can be set separately for each first cavity. This allows, for example, reduced hydrogen sulfide production by shutting off the supply of hydrogen to one or more first cavities. The reaction remaining in the first cavity can be continued at a constant hydrogen concentration and thus under certain reaction conditions. Optionally, with a certain total amount of hydrogen introduced, the hydrogen load can be distributed among several cavities or concentrated within the individual cavities to control the first cavity in a controlled manner. It can affect the reaction conditions in the section.

The reactor includes an outer, pressure-holding vessel. It preferably has the shape of an upright cylinder closed by a hood at each of the two ends. The reactor according to the invention preferably has a volume of 0.5 to 200 m ³ . The reactor according to the invention also has one or more feeding devices suitable for feeding liquid sulfur.

  The supply device for introducing hydrogen is preferably at the lower end of the reactor so that gaseous reactants flow through the reactor along its long axis.

Hydrogen introduced into the sulfur melt is saturated with gaseous sulfur and accommodated in the first cavity. In the gas space of the first cavity, hydrogen and sulfur are converted into hydrogen sulfide in an exothermic reaction, and a product gas mixture P ₁ containing hydrogen, sulfur and hydrogen sulfide is generated. The cavity is preferably surrounded by the sulfur melt so that the heat of reaction released in the cavity is dissipated into the sulfur melt.

“Cavity” in the context of the present invention is understood to mean any structural device capable of containing and holding a gas volume. The cavity can take the form of a hood-type installation device, for example, where a certain gas volume collects and flows down on the outer edge of the hood-type that opens downwards to a higher reaction area. Can do. In further exemplary embodiments, the cavity may be formed by a hollow body or a bed of irregular packing at various levels. For example, the hollow bodies or irregular packings may take the form of a sieve or a floor on a sieve box. Suitable hollow bodies or irregular fillings comprise, for example, straight or bent hollow cylinders, hollow spheres, deformed hollow spheres, bell-shaped objects, saddle-shaped objects, screw-shaped objects, or jagged and / or openings. Other three-dimensional objects. In order to allow the gas to permeate the holes or irregular packing of the hollow body, the hollow body and the irregular packing preferably have orifices on their outer walls and / or are made of a porous material. The The hollow body and irregularly packed bed according to the present invention preferably has a useful porosity (open porosity) Φ _open higher than 0.32, more preferably higher than 0.40, most preferably higher than 0.6. high.

  In a preferred embodiment, the cavity consists of a horizontal intermediate tray having one or more orifices through which gas can flow into the higher reactor region. Along the end of the orifice, the intermediate tray has a chamfer that runs vertically downward, said cage holding a particular gas volume within the cavity. FIG. 3 shows some exemplary embodiments of cavities useful in the present invention.

  The use of cavities in the form of a hood-type installation device or in the form of the horizontal intermediate tray described above is generally preferred for the use of cavities in the form of hollow bodies or irregularly packed beds. A disadvantage of hollow bodies or irregular packing is that by-product deposition of the reaction may occur during the long run time of the reactor under certain conditions, which causes the hollow body or irregular packing to It can be occluded. The use of cavities in the form of a hood-type installation device or in the form of a horizontal intermediate tray is suitable to avoid this possible disadvantage and thus contribute to extending the useful life of the reactor. Can do. In addition, this cavity design facilitates adjustment of the time for gaseous reactants to stay in the cavity, because parameters such as the cavity volume height to width ratio are more easily calculated. And it is changed.

  A further advantage of this cavity design is that when the hydrogen supply is reduced, the reaction gas itself does not escape completely from the cavity and the reduced hydrogen supply results in an increased residence time. This extension of the residence time is suitable to compensate for the reduction of the reaction temperature due to less hydrogen supply and thus to enable a constant high conversion. Thus, a cavity in the form of a hood-type installation device or in the form of an intermediate tray significantly increases the acceptable load range of the reactor.

Therefore, the load range of the reactor can be in the range of 0 to 4000 m ³ (STP) (H ₂ ) / (m ³ (volume of cavity) · h). The volume of the cavity relates in each case to the cavity through which the gas flows.

  The “first cavity” relating to the present invention relates to a cavity when the gas mixture collected in the cavity has not yet circulated through another cavity in advance.

  In an alternative embodiment, the supply device for introducing hydrogen is designed such that hydrogen can be introduced directly into the gas space of the first cavity that is not pre-saturated with sulfur. The reactor has a plurality of feeders per first cavity, some of which introduce hydrogen into the sulfur melt and others directly into the gas space of the cavity It may be configured to be introduced. This configuration scheme makes it possible to control the relative hydrogen concentration, i.e. the proportion of hydrogen and sulfur reactants in the first cavity. Furthermore, this configuration scheme can increase the amount of hydrogen and sulfur that fall within the optional second or more cavities described below.

In a preferred embodiment, the reactor includes, in addition to the first cavity, a second cavity that does not hold one or more pressures, the second cavity being a first cavity. In order to at least temporarily contain the product gas mixture P ₁ disposed above and in the first cavity, and further hydrogen sulfide is produced by the exothermic reaction of sulfur and hydrogen to produce product gas mixture P Suitable for ₂ to occur.

  With respect to the present invention, the “second cavity portion” relates to a cavity portion when at least a part of the gas mixture collected in the cavity portion flows through at least one first cavity portion immediately before.

In further embodiments, the one or more second cavities may include at least one supply device suitable for controlling and supplying pressurized gaseous hydrogen. In this way, gaseous hydrogen is introduced not only into the first cavity but also into the second cavity to increase the hydrogen concentration in, for example, P ₂ , and thus the reaction in the second cavity. Speed can be increased. The supply device, as in the case of the first cavity, allows hydrogen to be introduced either into the sulfur melt below the second cavity or directly into the gas space of the second cavity. Can be configured.

  In certain embodiments, the reactor is additionally provided with one or more non-pressure-holding third cavities disposed above the second cavities and optionally further correspondingly suitable cavities. Parts can be included.

  With regard to the present invention, the “third (fourth, fifth, etc.) cavity” means that at least a part of the gas mixture collected in the cavity is at least one second (third, fourth, etc.) immediately before. It is related with the cavity part at the time of distribute | circulating the cavity part.

  In order to increase the conversion rate of hydrogen in the second and higher cavities, it may be advantageous to extend the residence time of the hydrogen-containing gas mixture or to minimize the heat loss of the cavities. is there. To this end, at least one second or more cavity has a larger volume than each of the first cavities and / or at least one second or more cavity is first for structural reasons. The reactor can be designed to have a lower heat removal than each of the cavities. This is because it has been found that during the operation of the reactor, more than 60% of the hydrogen can already be converted in the first cavity. In that case, the above-mentioned means can achieve the effect that the hydrogen conversion rate is higher than 80% or even higher than 90% in the second cavity. Thereby, a high hydrogen conversion rate is achieved in the regions of the first cavity and the second cavity, so that the reaction proceeds in the gas space above the sulfur melt and the gas space above the sulfur melt. The effect of bringing about overheating is particularly avoided.

  Lower heat removal from the cavity for structural reasons can be achieved, for example, through the use of materials with lower thermal conductivity. The cavity may be made of this material, or at least part of its surface may be lined with this material. This backing can additionally form gas grooves that reduce heat transport. Less heat removal from the individual cavities can optionally be achieved by using a material having a larger material thickness.

  When the gas groove is used as a heat insulating material, the cavity portion can be lined with aluminum or an aluminum alloy to improve the corrosion resistance of the material of the cavity portion.

  In a further preferred embodiment, less heat removal from individual cavities is achieved by using a cavity geometry that prevents heat removal. For example, heat removal can be reduced by lowering the ratio of cavity surface area to cavity volume.

In a preferred embodiment, the first cavity has a surface to volume ratio of 1.5 to 30 m ⁻¹ , preferably 3 to 9 m ⁻¹ , more preferably 4 to 6 m ⁻¹ , and / or a height to width ratio. 0.02 to 5, preferably 0.05 to 1, more preferably 0.08 to 0.12, and / or the ratio of crest length to throughput 0.1 to 10 m * h / t _H2S , preferably 0 .2 to 1.8 m * h / t _H2S , more preferably 1.0 to 1.2 m * h / t _H2S . In a further preferred embodiment, the second cavity of the at least one ratio 1.5~30m surface to volume ^-1, preferably 2.8～9M ^-1, more preferably 3 to 5 m ^-1, and / Or a height to width ratio of 0.02 to 5, preferably 0.05 to 2, more preferably 0.1 to 1, and / or a cough length to throughput ratio of 0.1 to 10 m * h / t _H2S , preferably 0.15 to 1.8 m * h / t _H2S , more preferably 0.2 to 1.1 m * h / t _H2S .

During the operation of the reactor, the product gas mixture _Pu collects on the sulfur melt and from there enters the gas collection area of the reactor. In a preferred embodiment of the reactor, the gas collection area is located above the lower reactor area. In alternative embodiments, the gas collection region may be located, for example, below the lower reactor region, in the lower reactor region, or on the side of the lower reactor region.

In a preferred embodiment, the reactor may additionally comprise a mounting device that does not hold one or more pressure than the apparatus, the total amount of the product gas mixture P _u generated in the reactor region below It is suitable for continuously transported to the gas collection area, and, when the catalyst is present in the mounting device, and a product gas mixture of sulfur and hydrogen still present in the P _u to hydrogen sulfide Suitable for reacting with.

  One or more installation devices preferably take the form of a U-shaped tube. The reactor can include a plurality of identical or similarly configured tubes for transporting the product gas mixture. The U-shaped tube is typically placed horizontally in the reactor with each of its two ends facing up. When the gas collection area is positioned above the lower reactor area, each of the tube ends protrudes into the gas collection area while the U-shaped portion of the pipe is in the lower reactor area. The tube can be connected to an intermediate tray that divides the lower reactor region from the gas collection region. Individual tube limbs may be of different lengths such that the end of the shorter foot is in the lower reactor region and the end of the longer foot projects into the gas collection region.

  In an alternative embodiment of the reactor, one or more installation devices take the form of straight vertical tubes. If the lower reactor region contains sulfur melt, the straight tube is preferably immersed in the sulfur melt and the gas space above the sulfur melt is in or below the lower reactor region. It arrange | positions so that it may connect with the gas collection area | region arrange | positioned.

The tube preferably has a diameter of 20 to 3000 mm, preferably 60 to 150 mm, more preferably 80 to 120 mm. The product gas mixture _Pu is fed into the lower reactor through an orifice which may be provided, for example, in the side wall of the tube or in the case of a U-shaped tube with unequal length limbs at the end of the shorter limb. Enter the tube from the area. In order to prevent liquid sulfur from entering the tube, the orifice is preferably located at a distance of 0.1 to 3 m, preferably 0.4 to 1.4 m, on the sulfur melt interface. The product gas mixture flows along the tube and enters the gas collection region, for example, through an orifice provided at the end of the tube.

One or more installations preferably contain a heterogeneous catalyst for further converting the hydrogen and sulfur present in the product gas _Pu into hydrogen sulfide. Typically, cobalt and molybdenum containing catalysts are used. This is preferably a sulfur tolerant hydrogenation catalyst, preferably composed of a support such as silica, alumina, zirconia or titania, and one or more active metals molybdenum, nickel, tungsten, iron , Vanadium, cobalt, sulfur, selenium, phosphorus, arsenic, antimony and bismuth. A tablet type mixed compound composed of CoO, MoO ₃ , Al ₂ O ₃ with or without sulfate is particularly preferred. The catalyst is preferably arranged in the form of a fixed bed. In this case, the heterogeneous catalyst takes the form of pellets, tablets or similar shaped bodies. However, other designs are possible, such as honeycombs or fluidized beds. The catalyst can also be present as a coating on the irregular packing, monolith or knit in the installation.

The amount of catalyst placed in the installation device depends on the amount of residual hydrogen to be converted, the size of the installation device, the type of catalyst and possibly further factors. In the case of a catalyst bed, depending on the amount of hydrogen supplied, the amount of catalyst used has a hydrogen load of 4000 m ³ (STP) (H ₂ ) / (m ³ (catalyst bed volume) · h). Should not exceed.

  Furthermore, additional catalysts may be provided at one or more sites in the reaction vessel. In this case, the catalyst is preferably arranged so that it does not come into contact with liquid sulfur. The catalyst may be in the form of a pellet bed, in the form of a powder suspended in liquid sulfur, or in the form of an irregular packing, monolith or knitted coating. If an additional catalyst is used, this catalyst may be provided in an internal structure that serves as a cavity. In a further embodiment, the catalyst may be provided over liquid sulfur and all cavities.

In a preferred embodiment of the present invention, at least one of the mounting device for transporting the product gas mixture P _u from the reactor region below the gas collection area, in terms of structure, the reactor region below the sulfur If the installation device contains a catalyst so that it is in thermal contact with the sulfur melt after it has been sufficiently filled with the melt, the catalyst is cooled by the transfer of heat to the sulfur melt. Be placed. In the case of the U-shaped or straight tubes described above, they preferably have an outer shell region in the region of the tube filled with catalyst, to a degree of more than 20%, preferably 50%, depending on the sulfur melt. Surrounded to a degree of more than%, more preferably to a degree of more than 75%.

  In order to ensure an essentially homogeneous temperature distribution within the reactor, the reactor preferably includes an inner wall, and during operation of the reactor, the space between the outer and inner walls of the reactor is involved. The continuous circulation of the sulfur melt is possible by the principle of the air lift pump. Sulfur carried by the introduction of upward hydrogen from the bottom in the reactor region surrounded by the inner wall flows here and to the bottom in the space between the reactor outer and inner walls. The downward flowing sulfur can be cooled by removal of heat through the reactor outer wall. In a preferred embodiment, the cooling of the downward flowing sulfur is assisted by a heat exchanger provided, for example, on the reactor outer wall or in the space between the reactor outer wall and the inner wall.

In a preferred embodiment, the reactor comprises a reflux condenser suitable for the condensation of sulfur present in the product gas mixture P _final . The reflux condenser is preferably located above the gas collection area. The reflux condenser is connected to the gas collection zone via an input line suitable for transporting the product gas mixture P _final from the gas collection zone to the reflux condenser, and the condensed sulfur is fed to the reactor. Preferably having a return line suitable for return to the lower reactor zone. The return of the condensed sulfur also serves to cool the sulfur melt and thus contributes to maintaining the sulfur melt at a constant temperature.

  Even during long-term operation for several years or decades, the reactor according to the invention should be maintained or rarely repaired. The structure according to the invention avoids the generation of excessive temperatures in the pressure-carrying parts and thus increases the safety of the plant, because the reduction of corrosion in this area is due to the leakage of harmful substances such as hydrogen sulfide. This minimizes the risk of material damage and the possibility of accidents. Fewer requests for inspection, maintenance and repair reduce costs and improve availability.

The present invention is a method for producing hydrogen sulfide in which a product gas mixture P _final containing hydrogen sulfide and sulfur is produced by an exothermic reaction of sulfur and hydrogen at an elevated temperature and elevated pressure relative to standard conditions. In the following stages:
Providing a sulfur melt in the reactor region below the pressurized reactor;
Pressurized hydrogen is fed into the sulfur melt, and the fed hydrogen is at least partially by the first cavity that does not hold at least two pressures with the sulfur converted to gaseous form from the sulfur melt. Stage accommodated in,
Hydrogen and sulfur remain at least temporarily in the first cavity, and in an exothermic reaction, a product gas mixture P ₁ comprising hydrogen sulfide, sulfur and hydrogen is produced,
The product gas mixture P ₁ generated in the first cavity remains at least temporarily in the at least one second cavity and the sulfur and hydrogen present in the product gas mixture P ₁ react caused additional hydrogen sulfide, the method step product gas mixture P ₂ results, and - the product gas mixture P _final comprising collecting the gas collection area is also provided.

  The process is preferably carried out in the reactor according to the invention already described.

  It is also possible for contaminated hydrogen to pass through the sulfur melt rather than pure hydrogen. The impurity can be, for example, carbon dioxide, hydrogen sulfide, water, methanol, methane, ethane, propane or other volatile hydrocarbons. Preference is given to using hydrogen having a purity higher than 65% with respect to the volume of the gas. Hydrogen or impurities in their reaction products are preferably not removed prior to the synthesis of methyl mercaptan and remain in the reaction mixture. The sulfur used may also contain various impurities.

  The pressure and volume of hydrogen supplied depends on the pressure at which the reactor is operated and on the volume of hydrogen required. The amount of sulfur used is substantially the stoichiometric composition ratio to the amount of hydrogen used. Consumed sulfur is replenished during the process.

In a preferred embodiment of the method, the product gas mixture is contained in at least one second cavity and remains at least temporarily in the product gas mixture P ₁ and with the sulfur present in the product gas mixture P _1. Reaction with hydrogen produces additional hydrogen sulfide, resulting in a product gas mixture P ₂ .

  In a further embodiment of the method, at least a portion of the hydrogen fed into the sulfur melt is housed directly in the at least one second cavity. “Directly” is understood here to mean that the supplied hydrogen is not accommodated in the first cavity before entering the second cavity. In doing so, the supply of hydrogen can be controlled for the purpose of affecting the reaction rate differently in the first cavity and the second cavity.

The process is such that the product gas mixture is contained in at least one third or more cavity and remains at least temporarily such that the sulfur and hydrogen present in the product gas mixture P ₂ react to further hydrogen sulfide. Can be implemented.

  In an optional embodiment of the process, at least some of the hydrogen is fed into at least the first and / or higher cavities so that it does not come in contact with the sulfur melt beforehand. This makes it possible to increase the hydrogen concentration in the cavity without simultaneously transporting further sulfur to the gas space in the cavity.

  The supply of hydrogen into the liquid sulfur below the cavity (eg, the second cavity) is primarily due to the effect of increasing the hydrogen supplied to the cavity, and secondly, the sulfur is also from liquid sulfur. It has the effect of being transported to the gas space of the cavity.

In one embodiment of the method, the total amount of the product gas mixture P _u resulting in lower reactor region, contiguous with the one or the gas collecting area by mounting apparatus does not hold a lot of pressure than In this case, by using a catalyst in the installation device, sulfur and hydrogen present in the product gas mixture _Pu react to produce further hydrogen sulfide.

  The process is preferably carried out in such a way that the heat of reaction released by the reaction of sulfur and hydrogen is released as completely as possible into the sulfur melt. This includes the heat of reaction released on the catalyst. Therefore, the catalyst is preferably cooled by heat transport of the reaction heat released by the reaction of sulfur and hydrogen in the catalyst to the sulfur melt.

The preferred method, the proportion of hydrogen sulfide in the product gas mixture P _u before introduction into mounting apparatus containing the catalyst is at least 60% of the gas volume, carried to as preferably at least 90% . The process conditions required for this are described below. This has the advantage that a low proportion of hydrogen in the catalyst region prevents overheating of the catalyst and thus extends the useful life of the catalyst.

The process preferably comprises additional process steps in which the sulfur present in the product gas mixture P _final is condensed and recycled directly to the reactor, preferably to the lower reactor zone. As a result, there is an advantageous effect that cooling of the sulfur melt occurs depending on the amount of hydrogen sulfide produced. More specifically, at the instant the temperature of the sulfur melt increases, the hydrogen conversion, sulfur volatilization and sulfur reflux also increase, thus canceling the sulfur melt overheating. The condensation of sulfur is preferably carried out at a temperature of 120 to 150 ° C.

  The process according to the invention can typically be carried out at a pressure of 1 to 30 bar, preferably 5 to 15 bar, more preferably 7 to 12 bar. The temperature of the sulfur melt is typically 300 to 600 ° C, preferably 380 to 480 ° C, more preferably 400 to 450 ° C. Therefore, a hydrogen conversion rate of 99.9% can be easily achieved. Hydrogen conversion in the range of 99.93% was also observed.

The process according to the invention makes it possible to produce hydrogen sulfide having a purity higher than 99.8% by volume. Purities up to 99.85% by volume were also found. In this case, the product gas mixture after condensation of the sulfur present may contain 0.05-0.15% by volume hydrogen, 10-30 ppm sulfur, and 400-600 ppm sulfane. Sulphane in the context of the present invention relates to hydrogen polysulfide according to the empirical formula H ₂ S _x (where x is typically an integer from 2 to 10). The sulfur concentration mentioned above is already possible by condensation of sulfur within the temperature range mentioned above. Freezing at temperatures below 120 ° C. (known from other H ₂ S processes) is not required for this purpose.

  The invention also relates to the use of the reactor according to the invention for the production of hydrogen sulphide whose sulfane content does not exceed 600 ppm, preferably does not exceed 400 ppm, more preferably does not exceed 200 ppm.

The invention is further illustrated by the following examples:
1. At an elevated temperature and elevated pressure relative to standard conditions, an exothermic reaction of sulfur and hydrogen results in a _final product gas mixture P _final containing hydrogen sulfide and sulfur, which is a continuous hydrogen sulfide. A reactor (1) suitable for production comprising:
A lower reactor region (2) suitable for containing the sulfur melt (3), and to accommodate the product gas mixture P _final at an elevated temperature and elevated pressure relative to standard conditions. Gas collection area suitable for use (6)
At least two first cavities (4) that do not maintain pressure, and at least one supply device suitable for controlling and supplying gaseous hydrogen pressurized for each first cavity (5, 5a), said first cavity (4) is suitable for at least temporarily containing a product gas mixture P ₁ generated in an exothermic reaction and comprising hydrogen sulfide, sulfur and hydrogen. The reactor as described above.

2. The reactor (1) further includes a second cavity (8) that does not hold one or more pressures, the second cavity (8) being of the first cavity (4). In order to at least temporarily contain the product gas mixture P ₁ disposed above and in the first cavity, and further hydrogen sulfide is produced by the exothermic reaction of sulfur and hydrogen to produce product gas mixture P The reactor according to Example 1, characterized in that ₂ is suitable for producing.

  3. At least one of said second cavities (8) comprises at least one supply device (9, 9a) suitable for controlling and supplying pressurized gaseous hydrogen, Reactor as described in Example 2.

  4). The reactor (1) is further arranged on top of the second cavity (8), one or more third cavity (10) not holding pressure and optionally further correspondingly Reactor according to example 2 or 3, characterized in that it comprises an open cavity.

  5. At least one of the second or more cavities (8, 10) has a larger capacity than each of the first cavities (4) and / or at least one of the second or more cavities (8, 10). Reactor according to any one of examples 2 to 4, characterized in that one has a lower heat removal than each of the first cavities (4) for structural reasons.

6). Said reactor (1) further comprises an installation device (7) that does not hold one or more pressures, said device (7) being a product gas mixture produced in the lower reactor zone (2) If the total amount of P _u is suitable for continuous transport to the gas collection zone (6) and if a catalyst is present in the installation device (7), then in the product gas mixture P _u Reactor according to any one of examples 1 to 5, characterized in that it is suitable for reacting sulfur and hydrogen still present to hydrogen sulfide.

7). One, more than one, or all of the installation devices (7) for transporting the product gas mixture _Pu from the lower reactor region (2) to the gas collection region (6) When the installation device (7) contains a catalyst such that after the reactor zone (2) of the reactor is fully filled with the sulfur melt (3), they are in thermal contact with the sulfur melt (3). The reactor according to Example 6, characterized in that is arranged such that the catalyst is cooled by the transfer of heat to the sulfur melt (3).

  8). The reactor includes an inner wall (11), and during the operation of the reactor, the space between the outer wall and the inner wall (11) is involved, allowing continuous circulation of the sulfur melt by the principle of an air lift pump. Reactor according to any one of examples 1 to 7, characterized in that

9. The reactor further comprises:
A reflux condenser suitable for condensing the sulfur present in the product gas mixture P _final ,
Characterized in that it comprises an input line suitable for transporting the product gas mixture P _final from the gas collection zone to the reflux condenser, and a return line suitable for returning condensed sulfur to the reactor. The reactor according to any one of Examples 1 to 8.

10. A process for producing hydrogen sulfide, wherein a product gas mixture P _final containing hydrogen sulfide and sulfur is produced by an exothermic reaction of sulfur and hydrogen at an elevated temperature and elevated pressure relative to standard conditions, comprising: Stage of:
Providing a sulfur melt in the reactor region below the pressurized reactor;
Supplying pressurized hydrogen into the sulfur melt, and the supplied hydrogen is at least partially in the first cavity that does not hold at least two pressures with the sulfur converted from the sulfur melt into a gaseous state Stage accommodated in,
Hydrogen and sulfur remain in the first cavity at least temporarily, producing a product gas mixture P ₁ containing hydrogen sulfide, sulfur and hydrogen in an exothermic reaction, and gas collecting the product gas mixture P _final The method comprising the step of collecting in an area.

11. The product gas mixture P ₁ remains at least temporarily in one or more second cavities, and the sulfur and hydrogen present in the product gas mixture P ₁ react to react with further hydrogen sulfide. The process according to Example 10, characterized in that the product gas mixture P ₂ is produced.

  12 The method according to example 11, characterized in that at least part of the hydrogen fed into the sulfur melt is directly accommodated in one or more second cavities.

13. Said product gas mixture is contained in one or more third or more cavities and remains at least temporarily so that the sulfur and hydrogen present in the product gas mixture P ₂ react to further sulfidize. 13. Process according to example 11 or 12, characterized in that hydrogen is produced.

14 The total amount of product gas mixture P _u generated in the lower reactor zone is continuously transported to the gas collection zone by means of an installation device that does not hold one or more pressures, wherein said installation device 14. Any one of Examples 10 to 13, characterized in that the use of a catalyst in the reaction causes the sulfur present in the product gas mixture _Pu to react with hydrogen to produce further hydrogen sulfide. the method of.

  15. Process according to example 14, characterized in that the catalyst is cooled by heat transport of the reaction heat released by the reaction of sulfur and hydrogen in the catalyst to the sulfur melt.

16. The proportion of the hydrogen sulfide of the product gas mixture P _u before introduction into mounting device containing catalyst, characterized in that at least 60% of the gas volume, the method described in Example 14 or 15.

17. Any one of Examples 10 to 16, characterized in that it contains additional process steps in which the sulfur present in the product gas mixture P _final is condensed and recycled directly to the reactor. The method described in 1.

  18. 18. Process according to any one of examples 10 to 17, characterized in that the production of hydrogen sulfide is carried out at a pressure of 5 to 15 bar.

  19. The process according to any one of Examples 10 to 18, characterized in that the temperature of the sulfur melt is 400-450 ° C.

  20. 20. A process according to any one of examples 10 to 19, characterized in that the sulfur melt is circulated continuously according to the principle of an air lift pump.

  21. Use of the reactor according to any one of Examples 1 to 9 for the production of hydrogen sulfide whose sulfane content does not exceed 600 ppm.

FIG. 3 shows a reactor that can be used to produce hydrogen sulfide from hydrogen and sulfur according to the present invention. FIG. 4 shows a schematic of four different exemplary cavity arrangements for a reactor having a first cavity, a second cavity, and a third cavity. FIG. 6 schematically illustrates an exemplary embodiment of a cavity.

  FIG. 1 shows, by way of example and diagrammatically, a reactor that can be used to produce hydrogen sulfide from hydrogen and sulfur according to the present invention.

The reactor 1 shown in FIG. 1 comprises an outer, pressure-containing vessel containing a sulfur melt 3 in its lower region 2. Hydrogen can be introduced into the sulfur melt using the supply device 5, and the hydrogen is accommodated directly in the first cavity 4. Further, the supply device 5 a can be used to introduce hydrogen directly into the gas space 12 of the first cavity 4. In the gas space 12 of the first cavity 4, a product gas mixture P ₁ containing hydrogen, sulfur and hydrogen sulfide is generated. The reactor shown also has an additional feeding device 9, whereby hydrogen can be fed directly into the second cavity 8, whereby a product gas mixture P ₂ is produced in the gas space 13. Hydrogen can also be introduced directly into the gas space 13 of the second cavity 8 using the supply device 9a. The upwardly flowing gas mixture is temporarily accommodated in the third cavity 10, whereby a product gas mixture P ₃ is produced in the gas space 14. Product gas mixture as a whole P _u generated in the reactor region below collects in the gas space 15. The gas space 15 is separated from the gas collection area 6 by an intermediate tray 16. Product gas mixture P _u is transported from the gas space 15 by using the mounting device 7 into the gas collection region 6. The installation device 7 is designed as a U-shaped tube immersed in the sulfur melt 3. Gas can flow into and out of the installation device 7 via the orifices 17 and 18. Installation device 7 can accommodate the catalyst which allows the product gas mixture P _u in sulfur and further converted so the product gas mixture P _final by the hydrogen is caused. The product gas mixture P _final comprising sulfur and hydrogen sulfide is contained in the gas collection zone 6 and can be removed from the reactor via an orifice 19 or optionally fed to a reflux condenser. . In the region of sulfur melt, the reactor also includes an inner wall 11 which serves to circulate the sulfur melt continuously according to the principle of an air lift pump.

  FIG. 2 shows a schematic of four different exemplary cavity arrangements for a reactor having a first cavity, a second cavity, and a third cavity. The cavity is composed of intermediate trays each having one orifice. The orifices are each arranged to ensure that the gas mixture flows from the first cavity to the second cavity and from the second cavity to the third cavity. In the upper left is a reactor according to the invention having a first cavity, a second cavity and a third cavity, respectively. Each of the three cavities has the same geometric shape. Upper right, first cavity, second cavity, respectively, where the crest height increases continuously, thus increasing the residence time of the gas mixture from the first cavity to the third cavity And a reactor according to the invention having a third cavity. In the lower left is a reactor according to the invention having a first cavity, a second cavity and a third cavity, each having all the same crest height. The second cavity has a circular orifice in the center of the intermediate tray. Lower right, first cavity, second cavity, respectively, where the crest height increases continuously, thus increasing the residence time of the gas mixture from the first cavity to the third cavity. And a reactor according to the invention having a third cavity.

  FIG. 3 schematically shows an exemplary embodiment of the cavity. The cavity shown has an intermediate tray with crests running along its edges. Various embodiments for the lower end of the cough A and the contour of the cough B are shown.

Examples Example 1 (Comparative Example)
1000 I (STP) / h of hydrogen was continuously introduced through a frit at the bottom into a tube having an internal diameter of 5 cm filled with liquid sulfur to a height of 1 m. Sulfur consumption was compensated by adding more metered liquid sulfur while keeping the filling level constant. Sulfur removed from the product gas stream by condensation was recycled to the area above the tube in liquid form. On the liquid sulfur, armored thermocouples for temperature measurement were provided at 10 cm intervals. While the reactor was electrically heated to 400 ° C. through the outer wall, there was a uniform temperature of about 397 ° C. in the sulfur. However, the thermocouple on sulfur showed a maximum temperature of 520 ° C. In addition, a sample of new material made of standard stainless steel (1.4571) was placed on top of the liquid sulfur at the highest temperature position. After about 400 hours of operation time, a sample of the material was removed and it showed severe corrosion phenomena in the form of delamination and mass loss.

Example 2 (comparative example)
Example 1 was repeated except that the liquid sulfur height was increased to 4 m. The maximum temperature value above liquid sulfur was retained. Similarly, a serious corrosion phenomenon occurred in the sample of the material.

Example 3 (comparative example)
Example 2 was repeated except that 15% by weight of powdered Co ₃ O ₄ MoO ₃ / Al ₂ O ₃ catalyst was suspended in liquid sulfur. The maximum temperature value above liquid sulfur was retained. Similarly, a serious corrosion phenomenon occurred in the sample of the material.

Example 4 (Comparative example)
The production of hydrogen sulfide was verified in a pilot plant. The pilot reactor was about 5.5 m high, about 0.5 m in diameter, and about 0.8 m ³ in volume. The pilot plant had four cavities of equal dimensions in series. 70 m ³ (STP) / h of hydrogen is continuously metered through the hydrogen supply device, which is a hydrogen load of 3700 m ³ (STP) (H ₂ ) / (m ³ It corresponds to (volume of the cavity) · h). While controlling the filling level, the consumed sulfur was replenished. Sulfur removed from the product gas stream by condensation was recycled to the reactor in liquid form. The pressure in the reactor was 12 bar. The temperature in liquid sulfur was 430 ° C. Each residence time in the cavity was 5 seconds. The H ₂ conversion rate by the homogeneous reaction in the cavity was about 90%. The temperature in the cavity and on the sulfur melt was measured by a thermocouple fixed and installed in the reactor. Under this circumstance, the highest temperature measured in the cavity was 479 ° C. On top of the liquid sulfur phase, no homogeneous reaction initiation was identified. The temperature of the gas above the liquid sulfur substantially corresponds to the temperature of the liquid sulfur, so there was no further requirement in the sheathing material that maintained the pressure in the gas phase region above the liquid sulfur.

At that time, as schematically shown in FIG. 1 (7), the gas phase flowed to and passed through the catalyst in the installation apparatus. The remaining hydrogen was converted substantially completely on the catalyst (total conversion of H ₂ : 99.86 mol%). The gas space velocity on the catalyst was 3700 m ³ (STP) (H ₂ ) / (m ³ (catalyst bed volume) · h). There was virtually no corrosion in the form of delamination or mass loss on the materials used. Samples of standard stainless steel (1.4571) material installed for comparison purposes had only moderate corrosion erosion.

(1) Reactor (2) Lower reactor region (3) Sulfur melt (4) First cavity (5, 5a) Hydrogen supply device to first cavity (6) Gas collection region (7 ) Installation device for transporting gas from the lower reactor area to the gas collection area (optionally containing catalyst)
(8) Second cavity (9, 9a) Hydrogen supply device to second cavity (10) Third cavity (11) Inner wall (12) Gas space in first cavity (13) First Gas space in the second cavity (14) Gas space in the third cavity (15) Gas space in the lower reactor region (16) Intermediate tray (17) Orifice (18) Orifice (19) Orifice

Claims (15)

At an elevated temperature and elevated pressure relative to standard conditions, an exothermic reaction of sulfur and hydrogen results in a _final product gas mixture P _final containing hydrogen sulfide and sulfur, which is a continuous hydrogen sulfide. A reactor (1) suitable for production comprising:
A lower reactor region (2) suitable for containing the sulfur melt (3), and to accommodate the product gas mixture P _final at an elevated temperature and elevated pressure relative to standard conditions. Gas collection area suitable for use (6)
At least two first cavities (4) that do not maintain pressure, and at least one supply device suitable for controlling and supplying gaseous hydrogen pressurized for each first cavity (5, 5a), said first cavity (4) is suitable for at least temporarily containing a product gas mixture P ₁ produced in an exothermic reaction and containing hydrogen sulfide, sulfur and hydrogen And the reactor (1) further includes a second cavity (8) that does not hold one or more pressures, the second cavity (8) being a first cavity Further sulfidation to accommodate at least temporarily the product gas mixture P ₁ disposed above (4) and formed in the first cavity (4) and by exothermic reaction of sulfur and hydrogen suited for the product gas mixture P ₂ occurs resulting hydrogen Wherein the are, the reactor.   At least one of said second cavities (8) comprises at least one supply device (9, 9a) suitable for controlling and supplying pressurized gaseous hydrogen, The reactor according to claim 1. The reactor (1) further includes one or more third cavity (10 ) that does not hold pressure and is disposed above the second cavity (8). The reactor according to claim 1 or 2.   At least one of the second or more cavities (8, 10) has a larger volume than each of the first cavities (4) and / or at least one of the second or more cavities (8, 10). Reactor according to any one of the preceding claims, characterized in that one has a lower heat removal than each of the first cavities (4) for structural reasons. The reactor (1) additionally comprises an installation device (7) that does not hold one or more pressures, said device (7) being a product gas produced in the lower reactor zone (2) If the total amount of the mixture P _u is suitable for continuous transport to the gas collection zone (6) and a catalyst is present in the installation device (7), then in the product gas mixture P _u Reactor according to any one of the preceding claims, characterized in that it is suitable for reacting sulfur and hydrogen still present in the hydrogen to hydrogen sulfide. The reactor includes an inner wall (11), and during the operation of the reactor, the space between the outer wall and the inner wall (11) is involved, allowing continuous circulation of the sulfur melt by the principle of an air lift pump. Reactor according to any one of claims 1 to 5 , characterized in that A process for producing hydrogen sulfide, wherein a product gas mixture P _final containing hydrogen sulfide and sulfur is produced by an exothermic reaction of sulfur and hydrogen at an elevated temperature and elevated pressure relative to standard conditions, comprising: Stage of:
Providing a sulfur melt in the reactor region below the pressurized reactor;
Supplying pressurized hydrogen into the sulfur melt, and the supplied hydrogen is at least partially in the first cavity that does not hold at least two pressures with the sulfur converted from the sulfur melt into a gaseous state Wherein pressurized gaseous hydrogen is supplied by at least one supply device for each first cavity,
Hydrogen and sulfur remain at least temporarily in the first cavity, and in an exothermic reaction, a product gas mixture P ₁ comprising hydrogen sulfide, sulfur and hydrogen is produced,
The product gas mixture P ₁ produced in the first cavity remains at least temporarily in one or more second cavities, so that sulfur and hydrogen present in the product gas mixture P ₁ Reacting with each other to produce further hydrogen sulfide, resulting in a product gas mixture P ₂ , and collecting the product gas mixture P _final in a gas collection area,
Including said method. At least a portion of the hydrogen fed into the sulfur melt is contained directly in one or more second cavities and / or one or more of the product gas mixtures third or more is contained in the cavity and at least temporarily remain in, characterized in that additional hydrogen sulfide occurs sulfur and hydrogen present in the product gas mixture P ₂ is reacted, in claim 7 The method described. The total amount of product gas mixture P _u generated in the lower reactor zone is continuously transported to the gas collection zone by means of an installation device that does not hold one or more pressures, wherein said installation device 9. Process according to claim 7 or 8 , characterized in that by using a catalyst in the interior, the sulfur and hydrogen present in the product gas mixture _Pu react with each other to produce further hydrogen sulfide. The proportion of the hydrogen sulfide of the product gas mixture P _u before introduction into mounting device containing catalyst, characterized in that at least 60% of the gas volume, the method according to claim 9. _11. Any one of claims 7 to 10 , characterized in that it comprises additional process steps in which the sulfur present in the product gas mixture P _final is condensed and recycled directly to the reactor. The method according to item. 12. Process according to any one of claims 7 to 11 , characterized in that the production of hydrogen sulfide is carried out at a pressure of 5 to 15 bar. The process according to any one of claims 7 to 12 , characterized in that the temperature of the sulfur melt is 400-450 ° C. 13. A method according to any one of claims 7 to 12 , characterized in that the sulfur melt is circulated continuously according to the principle of an air lift pump. Use of a reactor according to any one of claims 1 to 6 for the production of hydrogen sulphide whose sulfane content does not exceed 600 ppm.

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